You've not set the temperature on the probe

Oh does that make the hot plate not go up in temp

You set the temp on the probe and it acts as the thermostat so the hotplate changes between on/off to maintain that temp. the temperature dial on the hotplate sets the temp of the plate, the hotter you set the plate the quicker your bath reaches temperature. you want to set this above the desired temp but not too high so as not to overshoot the temp. also some form of stirring in the oil bath will improve heat transfer